From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vladislav Bolkhovitin <vst@vlnb.net>
Subject: Re: [RFC] relaxed barrier semantics
Date: Thu, 05 Aug 2010 17:11:56 +0400
Message-ID: <4C5AB89C.5080700__8299.41524793885$1281013943$gmane$org@vlnb.net>
References: <20100727175418.GF6820@quack.suse.cz> <20100727183546.GG7347@redhat.com> <4C4FE58C.8080403@kernel.org> <20100728082447.GA7668@lst.de> <4C4FECFE.9040509@kernel.org> <20100728085048.GA8884@lst.de> <4C4FF136.5000205@kernel.org> <20100728090025.GA9252@lst.de> <4C4FF592.9090800@kernel.org> <20100728092859.GA11096@lst.de> <20100802173930.GP16630@think>
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To: Chris Mason <chris.mason@oracle.com>,
	Christoph Hellwig <hch@lst.de>, Tejun Heo <tj@kernel.org>,
	Vivek Goyal <vgoyal@redhat.com>, Jan Kara <jack@suse.cz>,
	jaxboe@fusionio.com, James.B
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Chris Mason, on 08/02/2010 09:39 PM wrote:
> I regret putting the ordering into the original barrier code...it
> definitely did help reiserfs back in the day but it stinks of magic and
> voodoo.

But if the ordering isn't in the common (block) code, how to implement 
the "hardware offload" for ordering, i.e. ORDERED commands, in an 
acceptable way?

I believe, the decision was right, but the flags and magic requests 
based interface (and, hence, implementation) was wrong. That's it which 
stinks of magic and voodoo.

Vlad